1．He was hit by a falling tree that night and killed ________.
A．on the spot B．in a spot
C．under the spot D．on a spot
答案与解析：A 考查on the spot的用法。句意：那晚他被一棵倒下的树砸了，当场死了。on the spot“当场”。in a spot“在困难中”。
2．Peter must be ill.It's the only thing that can ________ his strange behavior.
A．lie in B．result from
C．account for D．explain about
答案与解析：C 考查动词短语辨析。句意：彼得一定病了，这是唯一能解释他诡异行动的原因。account for意为“说明……的原因”。lie in“在于”；result from“起因于”，其后跟原因，与句意不符；explain为及物动词，其后不加介词about。
