刚刚收到NIW 485 REF, 内容如下：
please submit a letter and/or other evidence, which estaablishes that you will continue to be engaged in the occupation of which the NIW is based. This evidence shall specify how you intend to serve in the national interest and confirm that you intend to carry out the terms and conditions of the underlying I-140 petition.
1.请问怎么准备这个ref？
2.现在我在一个公司做的和niw大致相关，但不是research, 有关系吗？
3.是很普通的ref吗？
非常感谢！