As the main inventions of modern technology, cell phone and computer are increasingly used in our daily life anytime and anywhere. Cell phone: On one hand, it has positive effects. For instance, we can use it for an emergency, to send messages to our friends, to make people keep intimacy in spite of long distance. On the other hand, it takes disadvantages to some extent. For example, radiation, drawing students’ attention in class, Computer: Like the cell phone, the computer is widely used in most of areas. With the rapid development of the modern technology, the computer appears portable ,functional and takes us entertainment.

  Can we live without cell phone or computer? Of course not. Imagining without cell phone and computer, we will be far away with the message world and we will become ignorant and backward. 

 
All in all, our life is keeping pace with the development of modern society. The cell phone and computer are turning the world into a small village where we can communicate with each other easily and simply. We are supposed to make full use of them.

Subject: Old Microscope

1.Use one eye to watch.

2.Can magnify cells 100 times.

3.Too heavy.

4.Need sun light.

5.Cells too dim

Subject: New Microscope

1.Can use two eyes to watch.

2.Can magnify cells 1000 times or more.

3.Easy to carry.

4.Can make light by itself.

5.Can see cells more clear.

Similar:

1.All can magnify cells.

2.All need light.

3.Not is electronic.

   The father of micorscope is Anton Van Leeuwenhoke,He was the first to see and describe what is cell look like,and he find the blood. The oldest micorscope is Leeuwenhoke micorscope. In 18th century Technical innovations improved microscopes, leading to microscopy becoming popular among scientists. Lenses combining two types of glass reduced the "chromatic effect" the disturbing halos resulting from differences in refraction of light.
   And we have electron micorscope,The introduction of the electron microscope in the 1930's filled the bill. Co-invented by Germans, Max Knoll and Ernst Ruska in 1931, Ernst Ruska was awarded half of the Nobel Prize for Physics in 1986 for his invention. In this kind of microscope, electrons are speeded up in a vacuum until their wavelength is extremely short, only one hundred-thousandth that of white light. Beams of these fast-moving electrons are focused on a cell sample and are absorbed or scattered by the cell's parts so as to form an image on an electron-sensitive photographic plate.
   Old micorscope magnified the object one hundred times. Now we have better micorscope in our class, those  micorscope can magnified object more then one hunderd times.