Halliday & Matthiessen (2014: 574):
Here the primary verbal group is again not a separate process; but this time it is a circumstantial element in the process expressed by the secondary verbal group. If we say Alice ventured to ask something, this means she did ask it; but she did so tentatively. (The doubtful one here is hesitate, which perhaps belongs with the ‘projection’ type as a mental process.) Probably all of these would turn out to be metaphorical … . One of the examples above is analysed in Figure 8-5.
Again, the table cells misrepresent the analysis of Finite and Predicator. The Predicator is tend to open and the Finite is 'do' ('present').