in the 1900's 和 in the 1900s的区别?

in 1900s 和 in the 1900s那个对? in the 1900's 和 in the 1900s的区别? in 1960's 和in the 1960s的区别 in 1720s和in the 1720s的区别 Don't play football in the s( ) .It's dangerous. in the 1980s,in the 1980's和in 1980s的区别 in the 19th 和in the 1980's She's the most t() movie star in the world we can't see the s--------- in the day. in the 1990s,in the 1990's和in 1990的区别 in 1990 和 in the 1990s的区别 in the 1940's和in the1940s一样吗? the （t）Sunday in May is Mother’s Day Don't swim in the l___ alone.It's dangerous. Don't swim in the river a( ) .It's dangerous it's the best t() for sports in a day our history teacher's house is in the c----,not in the t--- Who's the girl___black T--shirt?A.in B.in the C.of D.down