1.帮我辨析一下knockdown,knockoff,knockin,konckinto的意思2.非谓语动词中的现在分词做状语时,中间是不是一定有个逗号?如Theywenttothepark,singingandtalking.Havingdonehishomework,heplayedbasket-ball.3.get

Question

1.帮我辨析一下knock down,knock off,knock in,konck into 的意思
2.非谓语动词中的现在分词做状语时,中间是不是一定有个逗号?
如They went to the park,singing and talking.
Having done his homework,he played basket-ball.
3.get down to跟的是现在分词还是动词原形

Answer 1

1.knock down击倒,knock off撞倒,knock in把(钉子)钉入..., knock into偶然遇到
2.非谓语动词中的现在分词做状语时,中间不一定有个逗号.LZ举的第一个例子,逗号可以删去,而第二个例子,由于非谓语动词做状语、状语是一个句子而且提到了句首,所以要加逗号与主句隔开.
3.get down to的to是介词,所以后面跟的是现在分词或名词