按规律填一填。
9×1=9 ······( )个9相加,比10少1;
9×2=18 ······( )个9相加,比20少2;
9×3=( )······( )个9相加,比( )少( );
9×4=( )······( )个9相加,比( )少( );
9×5=( )······( )个9相加,比( )少( );
9×6=( )······( )个9相加,比( )少( );
9×7=( )······( )个9相加,比( )少( );
9×8=( )······( )个9相加,比( )少( );
9×9=( )······( )个9相加,比( )少( )。
二、根据乘法口诀写算式。
( )×( )=( )
三九二十七
( )×( )=( )
( )×( )=( )
四九三十六
( )×( )=( )
( )×( )=( )
七九六十三
( )×( )=( )
三、送信。
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