You have a friend who is learning Arabic -> How long has he been learning Arabic? 1. You have a friend who is learning Arabic. (how long/learn/Arabic?) 2. You have just arrived to meet a friend. She is waiting for you. (wait/long?) 3. You see somebody fishing by the river. (catch / any fish?) 4. Some friends of yours are having a party next week. (how many people/invite?) 5. A friend of yours is a teacher. (how long/teach?)