How____it is to see you again.A.happily B.pleased C.glad D.pleasantThe boy is too busy___with the toys___his mother come back home.A.to play;to seeB.to play;seeing

happily是副词 副词修饰形容词或者副词
pleased既可作形容词 又可作动词作形容词的时候为sb is pleased[(+at/about/by/with)][+to-v][+that]作动词是为pleased sb 让某人高兴
glad, 成年人用的多，见面客套话用
be glad to see you (do sth)....
pleasant1.某人发自内心的舒适满意。 2>某物某地方
令人高兴的。。。形容被参见方。。。。。
Sb be pleasant..
这句话翻译过来为很高兴见到你。选C

1. D 只有pleasant 能修饰 sth
2. 应该是 playing 和 to
be busiy doing
too... to
结构

D 这是个句式,是It is +adj.+to do sth.这个句式.四个词中A是副词,B是“感到高兴的”,主语应该是人,D是令人愉快愉悦的这个意思,而C亦应该主语为人.
下面的题应该是The boy is too busy playing with the toys to see his mother come back home.这个句子的意思是男孩太忙于玩玩具以至于不能看到他的妈妈回家来.首先这是个too----to结构,另外里面含两短语：be　busy doing 和see sb do sth
希望对你有所帮助

1c.how glad.再次见到你是多么的高兴。How glad it is to see you again=what a pleasant it is to see you again
2.B too……to……太……不能
The boy is too busy to play with the toys(when) seeing his mother come back home