In this section, each item consists of six sentences of a passage. The first and sixth sentences are given as SI and S6. The middle four sentences in each have been jumbled up and labeled as P, Q, R, and S. You are required to find the proper sequence of the four sentences and mark your response accordingly.

S1:There are various bases
P:  All bases do not dissolve in water.  
Q: An alkali is a base that dissolves in water.
R: Never taste or touch them as they may cause harm. 
S: They are soapy to touch, bitter, and corrosive.
S6: These are all basic properties of bases