Mark the letter A, B, C or D to choose the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions

Mark the letter A, B, C or D to choose the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions.
UNFORTUNATELY , there was a few people who were injured after the serious flood yesterday .
luckily
regrettably
sadly
unhappily
My class had to DELAY our trip to Trang An because of the extremely bad weather.
go on
go over
put off
get though
In the 1960s, scientists discovered how to make very light and THIN bags from plastic.
heavy
thick
slim
weight
We PUT OFF the picnic until tomorrow because it is raining
dellay
continue
stop
forget
There is only one correct sentence among four sentences . Choose the correct one
Australia is surrounding by over 8, 000 islands.
Australia surrounded by over 8, 000 islands.
Australia is surrounds by over 8, 000 islands.
Australia is surrounded by over 8, 000 islands.