在练习使用显微镜的过程中，当转动粗准焦螺旋使镜筒缓缓下降，直到物镜接近玻片标本时，眼睛一定要看着（　　）

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    Do you like travelling? Staying ____ (health) while ____ (travel) can help to ensure your trip is a happy and enjoyable one. ____ you are travelling abroad, here are the tips you need to make your trip much ____ (easy):

    Make sure you have got signed passport(护照) and visas. Also, before you go, fill in the emergency information page of your passport! Make two copies of your passport identification page. This will help a lot if your passport ____ (steal). Leave one copy at home with friends or relatives. Carry the other ____ you in a separate place from your passport.

    Read the Public Announcements or Travel Warnings for the countries you plan to visit. Get yourself familiar with local laws and customs of the countries to ____ you are travelling.

    Leave a copy of your itinerary(旅行日程) with family or friends at home so that you can be contacted in case of an emergency.

    Do not accept packages from strangers. Do not carry too much money or ____ (necessary) credit cards. If we make enough____ (prepare), we will succeed. Have ____ good time!