Answer: You didn't identify the houseplant so I can't make specific recommendations (based upon the preferences of the plant) but I can give you some general advice. First, it's normal for evergreen plants to lose their oldest leaves. So if the oldest leaves, those at the bottom and towards the inside of the plant are yellowing and dropping, it's probably normal. If the new leaves are also affected, it indicates a cultural or environmental problem. Yellowing leaves can indicate too much or too little light; dry indoor air; drafts; under or over watering; or a need to be fed. Try to find out the name of your plant (visit your local garden center to see if there's one that's similar). Once you know what it is, submit another question to this forum and we'll explain the growing requirements of that particular plant. Then you can determine what the cause might be.
In the meantime, best wishes with your plant!
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