Why is there a tradition to write "b'Sham'achem", and to pronounce it k'Sham'achem?
Malbim: Once you hear the Teki'ah, immediately blow Teru'ah, so the sounds will mix.
What is "Tachteha"?
Rashi: [It will fall] in its place. Radak
Rachav's house was in the wall. It should have sunk into the ground. It says below (verses 22,23) that the Meraglim entered her house and took out her and her family!
Radak: The entire wall did not fall, only what faced Machaneh Yisrael. Her house was in the wall on another side, which did not fall.