学习语法首先要学习句子，因为句子是人类语言的核心，通过对句子的分析理解，可以更好的掌握语法。下面是小编整理的英语四级语法模拟练习(21)，希望对你的语法学习有所帮助！

　　201.This watch is _______ by hand, not by machine, so it is very expensive.

　　A.flat B.coined C.bored D.manufactured

　　202.These two horses look so much alike that we can not _______ one from the other.

　　A.differ B.detail C.distinguish D.defeat

　　203.The president of that company was very calm during the political _______.

　　A.failure B.fashion C.proceed D.crisis

　　204._______ is usually the chief enemy of the camera lens.

　　A. Occasion B.vain C.Moisture D.Deck

　　205.The _______ left the ship after sixty hours of hard struggle.

　　A.dash B.cell C.crew D.gay

　　206.On our way to Beijing, we visited Xi'an, a city of two million _______, and stayed there for two days.

　　A. insects B.human C.inhabitants D.flights

　　207.One of the main reasons for air pollution is that many cars _______ smoke into the atmosphere.

　　A.gather B.hire C.discharge D.escape

　　208.Don't forget to _______ to let us know you arrived safely.

　　A.cable B.cage C.border D.bay

　　209.She gave him a _______ that she could not come to his party.

　　A.mistress B.shoot C.neck D.hint

　　210.When the temperature is below zero, water will _______.

　　A.freeze B.virtue C.sink D.seek

　　201.D

　　202.C

　　203.D

　　204.C

　　205.C

　　206.C

　　207.C

　　208.A

　　209.D

　　210.A