4. He is _____, but he doesn't feel _____. Because he likes to surf the Internet for his study of English.
_____ you have the chance to study, you’d better make full use of your time.
Vincent van Gogh’s paintings were at last _____ as works of genius.
You should visit your parents _____, even when you are very busy.
I still remember ______ to the south where we attempted _____ the river, which proved to be dangerous.
—Please give me a call when you get home and let me know you are safe. —_____.