Muslim describes anything related to the religion of Islam.
Must means you absolutely have to do something. For example, "mom says I must clean my room".
Scientific name: sinapis hirta and brassica juncea
There are several different kinds of mustard plant. They are in the same family as canola, turnips and cabbages. A field of mustard flowering looks very much like a field of canola flowering.
Mustard is grown mainly for its seeds, although the leaves can be eaten too. Mustard seeds are ground up and mixed with vinegar and sometimes other spices to make the mustard you can buy in shops. Depending on the type of mustard used, mustard paste can be very sharp or very mild. Sometimes mustard, called wholegrain mustard, is made from the whole seeds of the mustard plant and a little oil instead of crushing the seeds to a paste.
A myth is a story that doesn't have a basis in reality, but that many people think is true. A good example of a myth is that you can catch a cold by going outside in cold weather.