忙しそうだった

seemed busy

→ 忙しい
phrase Common #7,220
seemed busy そう indicates that something appears to be the case; だった makes it past tense.
JA: 昨日は忙しそうだったね。
EN: You seemed busy yesterday.

メアリーは忙しそうだったとトムが言った。

Tom said that Mary seemed busy.

トム忙しそうだった?

Did Tom look busy?

トムはいつも忙しそうだった。

Tom always seemed busy.

忙しそうだったね。

You looked busy.