考：不定时、动名词（短语）“Wh- + to do" 和”名词性从句做主语“时，用单数形式。
但，从句为主语，主系表结构时，由表语的名词或代词决定。
eg, To see is to belive./ seeing is believing.眼见为实
What they need is not money,and what they need are good teachers.
他们需要的不是钱，他们需要的是好老师。
考：”分数/百分数 + of +名词“
eg, 70% of the funds were supplied by the goverment.
70%的资金是由政府提供的。
Half of the food has been sent to that area.
一半的十五已经被送往那个地区。
" a number of +名词” 复数形式
“the number of + 名词” 单数形式
eg, A number of children were playing in the park.
许多孩子在公园里玩耍。
The number of students in this school is rather small.
这个学校学生的人数量很少。
考：“a qunantity of; a lot of; lots of ; plenty of + 不可数名词或可数复数名词” 与名词一致。
“ quantities of + 名词”用复数形式
eg, A vast quantity of beer was sold yesterday.
A large quantity of drugs were found in his luggage.
Great quantities of sand were washed down the hillside by the rain.
" a great/good deal of ; a large amount of ; a bit of + 不可数名词“ 用单数形式。
考： ”one of + 复数名词+定语从句“用复数形式
当 one of 前 有”the only, the mere（仅仅） 等修饰时，用单数形式。
eg, Jeff is one of the jouralists who were awarded at that time.
杰夫是当时受嘉奖的新闻记者之一。
Jeff is the only one of the journalists who was awarded at that time.
杰夫是当时唯一受嘉奖的新闻记者。
