GRAMMAR DETAIL

～ました

did

Follows the connective form of a verb to politely express an action that occurred or was completed in the past.

Examples

昨日、友達に会いました。

I met a friend yesterday.

先週、家族と海へ行きました。

I went to the sea with my family last week.

Structure: Change a verb's polite ending ます to ました.
Basic usage: It politely reports an action in the past, as in 昨日、友達に会いました。.

Corresponding plain forms
- 会いました corresponds to 会った, and 行きました to 行った. Distinguish sound changes in the plain form from the stem used in polite forms.
Action and resulting state
- 窓を開けました reports the action of opening a window. It differs in focus from 窓が開いています, which directly describes the window as open now.