This is the first time astronomers ____the whole process of a black hole ___a star, from its firstto nearly final bites.A see eat B have seen eating C saw eaten D had seen eat 这个句式是不是用完成时呢?

This is not the first Around this world ,the last is first. This is my first bag中first前要加the吗 this is ____lesson 1.we first 2.us first 3.the our first 4.our first this is the first lesson=this is________. this is the first time this was the first time 怎么用,有什么区别? This has been the first time与this is the first time有什么区别 This is the first man ___(walk)to the moon . lesson the is first this week of the . This is the first two sections of the book. This is the first lesson ( )the new term day,term,of,this,the,the,is,first,new 英语翻译Hi Sarah,Sorry this is so late,I have been out of the country(China) for the past few weeks in Dubai in the UAE in the middle east,so your sister was right plus we only had limited access to the web,so this is the first time I have had ti This is My first This is the first time that I ______(be)there NO,This is the first time I chat with you This is the first time that I_the Summer Palace.(visit) the day this it is first term of造句