C 1題是said引導(dǎo)的賓主從句,后面是他們玩得很開(kāi)心,第二個(gè)空enjoyed themselves很容易就出來(lái)了（時(shí)態(tài)對(duì)應(yīng)said是過(guò)去式）,“他們玩得很開(kāi)心”是陳述句,所以引導(dǎo)詞用that
B 2題是tell引導(dǎo)的賓語(yǔ)從句（tell引導(dǎo)雙賓語(yǔ),us是間接賓語(yǔ),what they are talking about…是直接賓語(yǔ)變成的從句）,所以主句是who can tell us…,從句是what引導(dǎo)的那一句,根據(jù)從句用陳述句的原則,應(yīng)該將what are they talking over there 變成what they are talking over there（即提前的are要放回原位）
C 3題和2題的道理一樣.ask引導(dǎo)賓語(yǔ)從句,后面的句子應(yīng)為陳述句句型,除非是否定或強(qiáng)調(diào),否則陳述句句型是沒(méi)有助詞do或did
A 和上面兩題一樣,know引導(dǎo)的從句要用陳述句
C 首先,與上面相同,要用陳述句,然后,reach是及物動(dòng)詞,直接接賓語(yǔ),必須說(shuō)reach the post office,get才能與to連接接賓語(yǔ),get to the post office