主将从现常见的有以下四种情况：一、如果主句是一般将来时，那么从句常常用一般现在时。如：WhenIgrowup,I’llbeanurseandlookafterpatients.Ifitisfinetomorrow,wewillgoboating.二、如果主句是祈使句，那么从句通常要用一般现在时。如：Don’tlaughatmewhenImakeamistake.三、如果主句是含有情态动词的一般现在时，根据需要从句多用一般现在时如：Youshouldbequietwhenyouareinthereadingroom.常见的时间状语从句的连词有：assoonas,when,while,as,until等,条件状语从句的连词有：aslongas,unless,if等。Iwilltellhimaboutitwhenhecomes.注意：如果主句的时态是过去将来时，那么从句要用一般过去时。例如：Hesaidthathewouldhaveanothertryifhehadthechance.Iknewhecouldhelpmeifhewasfreethenextday.练习：（）1.IfyouwanttolearnEnglishwell,youmustuseitas___aspossible.A.oftenB.longC.manyD.soon（）2.---WhatwillBilldoifhe____inthetest?---Hewilltryagain.A.failB.failsC.willfailD.isfailing()3.Pleasetellherthenewswhenshe_____.OK,Iwill.A.comesB.willcome.C.comeD.wouldcome()4.Thestudentswillplanttreesifit___tomorrow.A.didn’trainB.hasn’trainedC.won’trainD.doesn’train()5.We__homeifthereisnobus.---Oh,whatapity!A.willwalkB.havewalkedC.walkedD.walk()6.Ifit_____tomorrow,I’llgobycar.A.rainB.willrainC.rainsD.wouldrain()7.IfMary_______nextSunday,wewillgoboatingtogether.A.willcomeB.comesC.shallcomeD.shouldcome()8.---Don’tforgettoaskhimtowritetome.---Iwon’t.Assoonashe_______,I’llaskhimtowritetoyou.A.willcomeB.cameC.comesD.iscoming()9.---_____theyounggirl_____theoldmancleanhisroomeveryday?---Yes,shedoes.A.Does;helpB.Has;helpedC.Did;helpD.Do;helps()10.---WhatdoesLindaoftendointheevening?---Sheoften_______herhomework,butontheeveningofMarch12she_______TV.A.does;watchesB.isdoing;watchedC.does;watchedD.isdoing;waswatching()11.Ourgeographyteachertoldusyesterdaythattheearth_______aroundthesun.A.wasmovingB.movedC.hasmovedD.moves()12.---Doyoulikethissilkdress?---Yes,Ido.It_______sosoftandcomfortable.A.isfeelingB.feelsC.hasfeltD.isfelt()13.---CanIgotoBeijingformyholiday,Dad?---Youcanwhenyou_______abitolder.A.willgetB.getC.aregettingD.got()14.Ifhe_______harder,hewillcatchupwithussoon.A.studyB.studiesC.willstudyD.studied()15.Frank_______toseehisgrandmaifhe_______freetomorrow.A.willcome;willbeB.comes;isC.willcome;isD.comes;willbe()16.–Whenwillyoutellhimthegoodnews?--Iwilltellhimaboutitassoonashe_______back.A.comesB.cameC.willcomeD.iscoming
