Heconcludedhisspeechwitharemarkthatfailure____themotherofsuccess.
A、musthavelastedB
【句意】本期設計聯絡會將持續十天才會結束。
【難點】by the time意指no later than the moment that something happens，常與過去完成時和將來完成時連用。
Thefirststepinthestudyofanylanguageisobservingand____preciselywhathappenswhennativespeakersspeakit.
The____ofAIDShasledtoanexpansioninresearchseekingacure.
It’snecessary______ustokeepourpetscleaneveryday.
-Wehaven’theardfromJaneforalongtime.
-Whatdoyousuppose_____toher?
Thelittleboydidn’tknow_______.
