1. The ________（纪念碑） is in honor of a scientist.
2. My parents thought it was ________（反常的） for a boy to be interested in ballet.
3. The young couple living next door often quarrel, which is really ________ （无法忍受的）.
4. Scientists have made a major _________（突破） in the treatment of cancer.
5. Try to act naturally, even if you’re _________ （紧张）.
