I noticed ___ at those beautiful flowers.
The restaurant must be crowded from ________number of cars parked in front of it,________?
As we know,Beethoven is the greatest musician ________.
A big disaster took place in ________1960s when I was in ________teens.
Scientists have found no ________of life on Mars so far,though great efforts have made on the research.
A lot of people were made tired of the lecture which ________as long as four hours.