い-adjectives
い-adjectives and their basic forms
い-adjectives change their own endings for negative and past meaning.
In plain language
Many describing words end in い, such as 赤い (“red”) and 寒い (“cold”). These are called い-adjectives. The describing word itself changes for “not” and “was.”
When to use it
Use them to describe colour, size, weight, weather, and how something feels. Add です at the end when speaking politely.
How to build it
For a polite statement, use the い-adjective + です. For “not,” change the final い to くない. For the past, change it to かった: 寒い → 寒かった. Do not put だ after an い-adjective.
A basic pattern
い → くない
Examples in context
The grammar point is shown in blue in each sentence.
このりんごは赤いです。このりんごはあかいです。This apple is red.
このかばんは重くないです。このかばんはおもくないです。This bag is not heavy.
昨日は寒かったです。きのうはさむかったです。It was cold yesterday.
Watch for this
今日は暑いだ。 → 今日は暑いです。
An い-adjective does not take だ.
Quick practice: い-adjectives
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