Can I use two sponsors when applying for a UK Standard Visitor visa?

...can I use two sponsors in applying for a UK Standard Visitor visa?

Yes, you may. There is no limit to the number of 3rd party sponsors an applicant can present. A benefactor can be an individual/family or a household or a company or any other type of entity that operates under a management scheme. As long as they are capable of providing an undertaking, it's allowed.

The controlling technical reference is Appendix V 4.3 of the Rules...

A visitor’s travel, maintenance and accommodation may be provided by a third party where the decision maker is satisfied that they...

While the rule is drafted in the singular, this is drafting convention only and not meant to exclude multiple sponsors. Commonly this is done by family members based in the UK and living in separate households with a shared interest in sponsoring the applicant. Each sponsor presents their credentials as enclosures to the application.

The classic case involves a parent with two or more children who are settled in the UK. In this case the children pool their resources together to sponsor the parent. Each sponsor must qualify in their own right.

Sponsors can 'mix and match', one can provide accommodation and another can provide transportation for example.

The mirror image works also: a single sponsor can attest for multiple applicants.

Adding by necessity: Sponsored applications are weak to begin with; UKVI tends to view them with scepticism and sponsors do not relieve the applicant of qualifying in their own right. The bulk of refusals in the archives here are sponsored applications (with single and multiple sponsors) and invariably contain formulae along the lines of...

...I acknowledge your sponsor proposes to pay for your visit, however, it is the circumstances of the applicant that remain paramount when assessing your application...

or...

...however whilst I take that into account in assessing your proposed maintenance and accommodation in the UK, that is only one aspect of the visitor rules and this sponsorship does not satisfy me of your own intention to leave the UK on completion of your visit...

As a general rule of thumb, each additional sponsor increases the complexity of a given application and hence reduces its likelihood of success. Avoid 3rd party sponsorship, and especially multiple 3rd parties if at all possible.