English for Writing Research Papers

9.3   Toning down verbs
There are some verbs that leave no room for doubt, for example: is / are, means, 
equals, demonstrates, proves, manifests.
 
S1.  This factor is responsible for the increase in ...
 
S2.  These results demonstrate the importance of ...
 
S3.  These findings are conclusive proof that x = y.
 
S4.  This problem manifests itself in …
 
S5.  This means that x = y.
S1–S5  give  the  reader  no  space  to  choose  another  possible  interpretation.  Such 
claims are very strong when used in reference to your own findings, but may be fine 
when talking about the literature.
Softer versions of S1–S5 are in S6–S10, respectively.
 
  S6.  This factor may be / is probably responsible for the increase in ...
 
  S7.  These results would seem to show / indicate / suggest the importance of ...
 
  S8.  These findings provide some evidence / appear to prove that x = y.
 
  S9.  This problem tends / seems / appears to manifest itself in ...
 
S10.  This seems likely / probable / possible that x = y.
S7–S9 make use of two verbs, the first (seem, appear, tends) reduces the power of 
the second (show, prove, manifest). Other useful verbs with a similar function are: 
help, contribute, have a tendency,
 and be inclined.