根据所给的句子以及汉语释义，用所学过的单词或短语完成句子，每空一词。
小题1:________ ________ ________(直到现在)，we have finished Book 4.
小题2:We are not allowed to ________ ________(参考)our notes in the exam.
小题3:His laziness can perfectly ________ ________(为…做出解释) his failure.
小题4:No one knows exactly how the fire ________ ________（爆发）last night.
小题5:Women are still being ________ ________ ________（看不起）in some areas.
小题6: It was hard for him to ________ ________ (挑出)his teacher in the crowd.
小题7:Keep on working like this and you will succeed ________ ________(迟早).
小题8: ________ ________ ________ I know (据我所知)，he is from America.
小题9:They ________ ________ ________(屏住呼吸) and watched the cat closely.
小题10:With so many animals ________ ________(灭绝)，the environment is becoming worse and worse.
小题1:Up to now
小题2:refer to
小题3:account for
小题4:broke into
小题5:looked down upon/on
小题6:pick out
小题7:in time
小题8:As far as
小题9:held their breath
小题10:dying out
小题1:Up to now 固定词组:直到现在up to now
小题2:refer to 固定词组：参考；查阅；涉及；refer to
小题3:account for 固定词组：解释account for
小题4:broke out 固定词组：爆炸；break out;本句是过去时。
小题5:looked down upon/on 固定词组：看不起look down on/upon
小题6:pick out 固定词组：挑出pick out
小题7:in time 固定词组：及时in time
小题8:As far as 固定句型：as far as I know据我所知
小题9:held their breath 固定词组：屏住呼吸hold one’s breath。根据watched说明本句使用过去时。
小题10:dying out 固定词组:灭绝die out；本句是with复合结构，与animals构成主动关系，故使用现在分词的形式。