This is the 6367th most frequent Chinese word.
托馬斯
"Thomas" (a transliteration of the name).
Here, '托馬斯' is used as a proper noun denoting a person's name.
托馬斯正在学习中文。
Thomas is learning Chinese.
In this sentence, '托馬斯' again serves as a proper noun and is in the possessive form indicating ownership or relation (his friends).
托馬斯的朋友都很喜欢他。
Thomas's friends all like him.
Here, '托馬斯' might indicate a location related to Thomas, depending on the intended meaning, yet clarifying the context is advisable for accuracy.