I read the words Tsinghua University, so 1 sec can finish it.

Brainstorming originated in ancient India. When thinking encounters special obstacles, we should quickly leave the habit of thinking and think about the problem from other aspects.

So this brain teaser should not be confined to the general meaning of reading Tsinghua. This is not to say that it takes time to get a diploma after reading Tsinghua, but literally, how long does it take to open your mouth and read Tsinghua?

Answer skills:

The difficulty of this question is that many respondents think that water or other tools are needed to put out the fire. Once they think in this direction, they can't find the right answer.

This problem is solved by adding words in crossword puzzles, that is, adding one Chinese character to other Chinese characters.

When answering brain teasers, don't think too far in one direction. Once found, we should change our thinking immediately, otherwise we will fall into the trap of topic setting.

Reference to the above content: Baidu Encyclopedia-Tsinghua University