welcome sb to do的用法不对。welcome作动词是欢迎某人来某地的意思，后面要加地点。非要用welcome的话，可以说sb be welcome to do sth。
sb be welcome to do sth例句：I hope enterprises of the two countries will enhance their cooperation，Trinidad and Tobago companies are welcome to do business in the Chinese market（我希望两国企业加强合作，欢迎特多企业到中国开拓市场）。
