Take a lot of air. Place the tip of your tongue against the palate, just above your upper teeth. Exert pressure to try to expel the air but do NOT let it come out either on the sides of the tongue (you will produce an "l") or through any aperture between the tongue and the palate (the result will be /tch/). Now, take a lot of air, relax the tip of the tongue and try to pronounce /t/ sounds one after another as fast as possible; train your tongue to flap quickly and ever faster against the palate in that way; next take air and try to say /tr/ from the same position; a sort of /rrrrr/ sound will gradually emerge. Then, instead of trying to produce "tr", take as much air as you can, hold it, and try to expel it in that way by simply letting the tip of the tongue flap quickly against the center of the palate. Four or more flaps should produce an "rr" sound, :-). Less than that yields a simple "r" sound.

R = ere or erre

oh ya .it's hard for chinese people . 轻轻卷起舌尖,然后自然发气....放松 不知你小时候有无玩过学"摩托车"那种声音.如果会发那种声音就很快学会.只需要把震动提前到舌尖就行了.还有就是开始学时把头向后仰..... 我就是这样练会的... 是主要是靠感觉!! 我也在上海学西语.你在哪个学校?

put the top of your tongue in the palate leaving a small space up to the teeth and make vibrate the tongue... in spanish "r" or "rr" are very similars... don´t worry, spanish people is very tolerant with foreigner´s pronunciation¡. good luck

In spanish the sounds r and rr are same, you can speak with a native like me and to copy the sound