(1) secretly

(2) Manufacturing method (technology)

(3) Only, only

9.

So far/carpentry/have used pre-materials as a method.

10.B

1 1.

(1) So the tiles were laid on the tower, but the wooden tower was still shaking as before.

(2) When the tower was first built, it didn't look straight, but tilted to the northwest.

12.

(1) Yu Hao has a profound understanding of the characteristics and stress of wood structures. Although he didn't go to the scene in person, he can still accurately point out the key to the problem, which shows that his practical experience is very rich.

(2) It turns out that Yu Hao did this on purpose. It can be seen that Yu Hao not only considered the technical problems of the project itself, but also paid attention to the influence of the surrounding environment and climate on the building.