Thai past experience: ever, never and dates

Have done it before

Put เคย before an action to say you have that past experience.

ผมเคยไปเชียงใหม่ says I have been to Chiang Mai before. เคย comes before ไป; it presents previous experience, not a plan to go or being there now. The action word stays the same.

ผมไม่เคยไปเชียงใหม่ means I have never been to Chiang Mai. Put ไม่ before เคย. Compare ผมยังไม่ได้ไปเชียงใหม่, I have not gone to Chiang Mai yet. The second often suggests a visit that is still expected, but does not guarantee it will happen.

คุณเคยทำอาหารไทยไหม asks have you ever cooked Thai food? Natural short replies are เคยครับ, yes, I have, and ไม่เคยครับ, no, I have not. The question tells us which experience the reply refers to. Add the familiar polite question ending in the feminine style when it fits the speaker.

The experience may be one occasion or more; this marker does not count how many. In other contexts it can also describe what someone used to do. Later story blocks develop that use.

A short reply depends on the action in the question.

Experience and a particular occasion

A time expression can locate a past event without an experience marker.

เมื่อวานผมทำอาหารไทย says I cooked Thai food yesterday. The time word locates an event; there is no compulsory ending on ทำ. ผมเคยทำอาหารไทย says I have cooked Thai food before, without naming a particular day.

เมื่อวานผมไม่ได้ทำอาหารไทย says I did not cook Thai food yesterday. In this past-event context, ไม่ได้ before the action says it did not happen. Do not automatically read this before-action pattern as inability; the next block teaches ability and permission patterns.

ผมเคยไปเชียงใหม่ปีที่แล้ว means I went to Chiang Mai last year. ปีที่แล้ว means last year. You can use เคย and still say when the experience happened. The time expression adds detail; it does not automatically make เคย wrong.

เมื่อวานผมทำอาหารไทย tells you what happened yesterday. ผมเคยทำอาหารไทย tells you I have done it before. Both can describe the same event, but they highlight different information.

เคย can appear with a past-time expression. Choose it for the experience you want to describe, not simply because a sentence is about the past.

Experience can still have a date

เคย tells your listener that you have done something before. You can also add when it happened, such as last year. The experience and its date give different pieces of information.