Question About 过 and 了
I am just an elementary user. Nonetheless, I was puzzled by your use of 过 and 了 in two recent lessons. In the Checking out of a Hotel lesson, the expansion sentences included: 我 一共去了五次。I would have used 过 in this sentence because going somewhere is a repeatable event in the past, more of an experience. I thought you used 了in this context when you went somewhere and had not yet returned.
Conversely, in the Getting Picked Up By a Driver lesson, in the expansion sentence 我问过老师了，I can't figure out why both 过 and 了 are used.
watyamacallitApril 18, 2011, 02:00 PM
The problem with the first sentence is that we don't know the context of the situation that the sentence is spoken in.
If the speaker was talking about how many times he went to the toilet yesterday, then it is definitely a 了 sentence - he has a definite time frame in mind.
If he was talking about how many times he has visited Beijing in his lifetime he would use 过. If he was talking about how many times he went last year, or in any nominated (or implied) year, he would use 了.
JohnApril 19, 2011, 02:15 AM
For the first sentence, you can also use 过, but it's a little different. It's like the difference between "Altogether, I went 5 times" (了) and "Altogether, I've been there 5 times" (过). Watyamacallit makes a good point with regards to context, though.
As for 我问过老师了, this sentence-final 了 is known as 了2, and it is often optional. In this case it can be dropped. It's used to reinforce the idea that a situation has changed; 15 minutes ago I hadn't asked yet, but now I've asked.