Don't worry.I will come back before long.改同意句Don't worry.I will_____ _____.怎么填空

Don't worry.I will come back before long.改同意句
Don't worry.I will_____ _____.
怎么填空

I will return soon.
come 不能表示回来,后面需加back

return soon

back soon .OK

come soon

Don't worry。I will back soon.
before long 不久后
long before 不久前

return soon
如要用back,前面应有be或come才正确