he was absent from class yesterday morning because he was so sick =>Because of..............

Đáp án: Because of being so sick, he was absent from class yesterday.

Hoặc: Because of his sickness, he was absent from class yesterday.

`@` Clause `1` because `+` clause `2`

`≈` Because of `+`  `N`/Phrase `N`

`@` Phrase `N`:

`-` `V-`ing

`-` her/ his/ my `+` (adj) `+` `N`

`-` the `+` `N`

`@` sick (adj): ốm

`→` sickness (n): bệnh tật

`\text{#Rain}`