I.

$1.$ What are the stilt house built on ?

What + be + S + V3 ?

$2.$ What did your father buy ?

What + trợ động từ + S + V ?

II.

$1.$ Chu Dong Tu are both lengendary saints; however, they are worshipped the different things.

S + V; however, S + V.

$2.$ Although the Buffalo-fighting Festival sounds frightening, it is an excited part of the ceremony to worship the Water God.

Although S + V, S+ V.

III.

$1.$ My sister isn't as good as swim as me.

$S_1$ + be + short adj + er/more + long adj + than + $S_2$.

→$S_2$ + be + not + as + adj + as + $S_1$.

$2.$ Phong runs the most quickly in his class.

Nobody/noone/... + be + short adj + er/more + long adj + than + S.

→S + be + the + short adj + est/most + long adj + N.

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