—Have you ever been to abroad as an exchange student(交换生)?
—No, I haven't.
A：to a big city
B：to a foreign country
C：to a different school
给字加偏旁或部首组字组词。
旬——____——____ 奂——____——____
孝——____——____ 咸——____——____
172×24－172×14=____
