Convert Sql to LINQ complex C# function to readable sql server string -

i read lot getting readable sql server query string c# linq sql function, not figure out how so, maybe because project working on complicated.

i'm pasting pice of code want convert sql (select * bonds join etc.)

public list<entbondportfolio> getbondsforportfolio(list<int> groups, list<int> ratings,   list<int> collaterals, list<int> companies, list<int> countries, list<int> fields,   list<int> currencies, datetime? fromexpirationdate, datetime? untilexpirationdate, bool? perpetual, int? sortorder = 1) {  // bonds  return (from bond in dallinqclasses.instance.bonds          join company in dallinqclasses.instance.companies on bond.company_id equals company.companyid          companyjoin          companyj in companyjoin.defaultifempty()          join sellbuy in dallinqclasses.instance.sell_buy_operations on bond.bondid equals sellbuy.investment_id          join account in dallinqclasses.instance.bank_accounts on sellbuy.bankaccount_id equals account.bankaccountid          join groupstable in dallinqclasses.instance.groups on account.groupaccount_id equals groupstable.groupid          join customer in dallinqclasses.instance.customers on groupstable.customer_id equals customer.customerid          join rating in dallinqclasses.instance.ratings on bond.rating_id equals rating.ratingid          ratingjoin          ratingj in ratingjoin.defaultifempty()          join currency in dallinqclasses.instance.currencies on bond.currency_id equals currency.currencyid          join country in dallinqclasses.instance.countries on bond.country_id equals country.countryid          countryjoin          countryj in countryjoin.defaultifempty()          join field in dallinqclasses.instance.fields on bond.field_id equals field.fieldid          fieldjoin          fieldj in fieldjoin.defaultifempty()             join collateral in dallinqclasses.instance.risc_levels on bond.risclevel_id equals collateral.risclevelid          collateraljoin          collateralj in collateraljoin.defaultifempty()           join orderi in // order              dallinqclasses.instance.portfolio_orders.where(x => x.investmenttype_id == (int)investment_types.bonds)              on new enttwoints { bankaccountid = bond.bondid, groupid = groupstable.groupid }              equals              new enttwoints { bankaccountid = orderi.investment_id, groupid = orderi.group_id }              orderjoin          orderj in orderjoin.defaultifempty()           sellbuy.investmenttype_id == (int)investment_types.bonds          && groups.contains(groupstable.groupid)          && (collaterals.contains(bond.risclevel_id ?? -1) || collaterals.contains(-1))          && (ratings.contains(bond.rating_id ?? -1) || ratings.contains(-1))          && (companies.contains(bond.company_id ?? -1) || companies.contains(-1))          && (countries.contains(bond.country_id ?? -1) || countries.contains(-1))          && (fields.contains(bond.field_id ?? -1) || fields.contains(-1))          && (currencies.contains(bond.currency_id) || currencies.contains(-1))          && (bond.expirationdate >= fromexpirationdate || fromexpirationdate == null)          && (bond.expirationdate <= untilexpirationdate || untilexpirationdate == null)          && (perpetual == bond.perpetual || perpetual == null)            group sellbuy new { bond, companyj, groupstable, account, orderj, customer, ratingj, collateralj, countryj, fieldj } g           orderby g.key.orderj != null ? false : true, g.key.orderj.sortorder, g.key.groupstable.groupname, g.key.companyj.companyname          select new entbondportfolio          {              rating = g.key.ratingj.ratingname,              risclevel = g.key.collateralj.risclevelname,              group = g.key.groupstable.groupname,              client = g.key.customer.firstname + ' ' + g.key.customer.lastname,              groupid = g.key.groupstable.groupid,              company = g.key.companyj.companyname,              currencyid = g.key.bond.currency_id,              bondid = g.key.bond.bondid,                calltext = g.key.bond.calltext,              field = g.key.fieldj.fieldname,              country = g.key.countryj.countryname,                couponpercent = g.key.bond.couponpercent,              // total sum of coupons in checking account of current bond              couponspaid = dallinqclasses.instance.checking_accounts.                              where(x => x.actiontype_id == (int)action_types.coupon                              && g.select(y => y.sellbuyoperationid).                              contains(x.sellbuyoperation_id.getvalueordefault()))                              .sum(s => s.actualsum),              expirationdate = g.key.bond.expirationdate,              facevalue = (g.where(x => x.issell == false).sum(x => x.facevalue) - (g.where(x => x.issell == true).sum(x => x.facevalue) ?? 0)),              isin = g.key.bond.isin,              lastbuydate = g.where(x => x.issell == false).max(x => x.sellbuyoperationdate),              currentprice = dalinvestmenttypes.instance.getcurrentpriceofbond(g.key.bond.bondid, bonds_history_types.marketvalue),              currentyield = dalinvestmenttypes.instance.getcurrentpriceofbond(g.key.bond.bondid, bonds_history_types.yield),              currentacrinterest = dalinvestmenttypes.instance.getcurrentpriceofbond(g.key.bond.bondid, bonds_history_types.acrinterest),                purchaseprice = g.where(x => x.issell == false).sum(x => x.facevalue) == 0 ? 0 :              g.where(x => x.issell == false).sum(x => x.facevalue * x.price)              / g.where(x => x.issell == false).sum(x => x.facevalue),                instruction = dalinstructions.instance.isinvestmenthaveinstruction(investment_types.bonds, g.key.bond.bondid, g.key.account.bankaccountid),          }).tolist(); 

}