根据句意和所给中文写出句中所缺的单词。
1.—Where’s Mr. Green?
—He has gone to attend an__________(国际) meeting.
2. I write to my mother every week, __________(主要) on Sundays.
3. The heavy work ___________(影响) his health, so he looked much older.
4. Do you know the saying, “A friend in need is a friend __________(真正地).
5. It’s important to_____________(教育)the young students.