16 science physics chemistry biology power force gravity electricity gas solid liquid living things cell germ change flamePre-reading Look at the pictures. Who are they? Are they famous? What are they famous for?ArchimedesDarwinCurieNewtonArchimedes: Darwin: Curie: Newton:mathematics and physicsHe discovered buoyancybiologyHe discovered that the ancestors ofpeople were monkeysphysicsShe discovered radium andradioactivityphysics He discovered why all things fall down to the earth.They all need electricity.Who discovered the electricity?Benjamin Franklin (1706---1790)How did he discover the electricity?an American printer, author, diplomat, philosopher, and scientist Franklin’s Famous Kite Experiment things we need a kite bad weather( thunderstorm) a key a condenser a shed a handkerchief strings a key a silk ribbon two pieces of light wood a sharp piece of metal What do we need to make the kite? 1.build the frame by making a small cross 2.tie the corners to the points of the cross 3.add a tail to the frame 4.tie a long string to the cross 5.fix a sharp piece of metal to the top of the longer stick 6.fasten a key to the end of the long string 7.tie a silk ribbon to the string above the keyHow to make Franklin’s kite?ConsolidationConsolidationwooden sticks Kite experiment Silkhandkerchiefsilk ribbonkeya sharp piece of metalstringkitecondensershedbad weather 1 ． Why should students be careful smelling from bottles?be careful doing 的意思是“做某事仔细或小心”，be careful 后面常跟 with ， in ， about 等介词短语，也可跟 to do 或从句。例如：People should be more careful about the things they say.Be careful that the medicine is kept away from children.Please be very careful with those plates! 那些盘子，要十分小心。 2 ． W...
