根据括号中所给的汉语写出单词，使句子意思完整。(5分)

小题1:Those __________(猎人) camp in the forest to catch animals.

小题2:There are many_______(老鼠) in that box.

小题3:The three space       (英雄)returned to Beijing on September 29th．

小题4:My mother finished ________(做针线活)very late last night.

小题5:Abraham Lincoln was famous as one of the greatest_______(总统) of the USA.

若CT提示可能为动脉瘤性出血而DSA检查阴性，可能的原因有哪些?