when we use public document ,where do we see them

when we use public document ,where do we see them what is public document , when we use it快,求大家帮个忙 We can use 'when' when when do we use capital letter So we must be careful when we use the Internet. We use b__ to keep warm when it is cold. We may not know how to use the ____ when we need to contact with our family members .A bookB telephone C key D card We can use ____ of every piece of paper,especially when we are making notes.A.either sides B.some C.both sides D.most We use__or___before when we mention them for the first time.We use __when we mention them againA.the;a;an B./;a;the C.a;/;an D.a;an;the 求大神解析一道英语选择we'll discuss many situations___english beginners fail to use this expressionA.when B.on which C.where D.why The time has come ___________ we can make extensive use of nuclear energy.A.as B.when C.while D.since what shall we use for power when all the oil in the world has__________?a.given out b.put outc.held up d.used up When we talk about abilities in the past,we should use c______ we have to ___(is) useful when we use fire题目是不是有错? We can use c____ to take some photos when we go on a trip.怎么填 we use the subject form when the noun we are replacing is the subject.翻译 When we use computer,we can l____ a lot and k____ many things. what part of a watch do we use when we greet someone