Fit is a verb, and the present participle is fitting. Fitting has many usages and fixed collocations in English. Here are some common usages and examples:

1. is used as an adjective, meaning "appropriate", "appropriate" and "commensurate". For example:

This dress suits you very well )

The new sofa fits well in our living room. )

2. Used as a noun, meaning "fit" and "cooperate". For example:

I need to try on my wedding dress. )

The tailor is making clothes that fit me. )

3. Used as a verb, meaning "try on" and "try on". For example:

She is trying on a fitting in the fitting room. )

-The mechanic is putting new tires on my car. The mechanic is fitting new tires on my car. )

4. Used as a noun, meaning "attachment" and "accessory". For example:

-The shower head fittings are missing. The shower head fittings are missing. )

-The bicycle shop has all kinds of accessories suitable for your bicycle. The bicycle shop has all kinds of accessories suitable for your bicycle. )

5. Used as an adjective, meaning "tight" and "close". For example:

The door fits closely with the door frame. )

This lid fits this container perfectly. The lid and container are tight. )

In a word, fitting is a very common word, which has many usages and fixed collocations in everyday English. Mastering these usages and collocations can help us better understand and use this vocabulary.